Stackable marker



FIG. 1 is a perspective view of a stackable marker showing my new design;

FIG. 2 is a side elevational view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a front elevational view of a second embodiment of my design of FIG. 1;

FIG. 6 is a side elevational view of FIG. 5;

FIG. 7 is a top plan view of FIG. 5;

FIG. 8 is a front elevational view of a third embodiment of my design of FIG. 1;

FIG. 9 is a side elevational view of FIG. 8;

FIG. 10 is a top plan view of FIG. 8;

FIG. 11 is a front elevational view of a fourth embodiment of my design of FIG. 1;

FIG. 12 is a side elevational view of FIG. 11;

FIG. 13 is a top plan view of FIG. 11; and,

FIG. 14 is a bottom plan view of FIGS. 1, 5, 8, and 11. 

The ornamental design for a stackable marker, as shown and described. 